The World is Not Enough Walkthrough:
Masquerade

This is another semi-annoying sneak around mission. I don't like these because they reward you for just playing the mission over and over again until you figure out exactly where everybody walks. Real life doesn't work like that ;)

OK. Show your ID to the guard. Grab the card on the desk and now go back to the main hallway and head left, down the ramp, and right. Grab the bullets and armor.

Back to the hallway. Use the card you grabbed from the desk, wait for the guards, and then sneak past them. Run down the hall and stick the card into the slot. Now back to your first card, and show that to the guard. Isn't this fun?

Grab the radiation badge next. Yup, go and show it to the guard. Go in and press th eswitch, and back out and up to the main room. Get to Dr. Jones, and protect her from harm. A series of fights ensue, and then you grab the final chain with your grappling hook. You're out!